Mayock said each of the top three tackles -- Michigan's Taylor Lewan, Texas A&M's Jake Matthews and Auburn's Greg Robinson -- is "big, strong, fast, highly athletic." Analyst Brian Billick said "all three fit the term 'franchise tackle.'" And analyst/former NFL lineman Shaun O'Hara said "these three tackles might even be better" than last year's top three -- each of whom went in the top four of the draft (Eric Fisher, Luke Joeckel and Lane Johnson).

As for the offensive line group as a whole, Mayock said "we're just getting to see some unbelievable athleticism."

Robinson stood out to Mayock. Robinson, who measured 6-feet-5 and 332 pounds at the official weigh-in Friday, ran a 4.92-second 40-yard dash Saturday; that came one day after he had 36 reps at 225 pounds in the bench press.

Matthews (6-5, 308) ran a 5.07 40-yard dash, and draft analyst Charles Davis called him the "Secretariat" of the available tackles. "He has been schooled well in the run game and the pass game," said Davis, who said Robinson must improve in pass protection.

NFL Media analyst Daniel Jeremiah has Robinson is his top tackle. While acknowledging that Robinson needs to become better in pass protection, "I've seen enough of the athleticism" to think Robinson can become a good pass protector, Jeremiah said.

Lewan (6-7, 309) had the best 40 time: 4.87 seconds.

"The first three tackles put on a show today," Mayock said.

Mayock also spoke highly of Notre Dame's Zack Martin (6-4, 308), who didn't run the 40 because of a minor injury. "I think he can start at all five positions on the offensive line," Mayock said, noting that some teams think Martin -- who played left tackle at Notre Dame -- might be a Pro Bowl-caliber guard.

Mike Huguenin can be reached at mike.huguenin@nfl.com. You also can follow him on Twitter @MikeHuguenin.